Paolo Sartor’s research while affiliated with Centre for Theoretical and Applied Ecology and other places

The estimated impact of the EU Landing Obligation was investigated, which bans discards of regulated species, in South European fisheries through stakeholders' perceptions with the intention to identify implementation shortcomings and practicalities that might lead to obstacles to enforcement. Structured interviews were conducted with 173 fishers in 4 countries practicing 4 generic fisheries (as typified by the dominant fishing gear) asking a total of 26 questions. Results show that fishers estimate that the full implementation of the discards ban will result in longer sorting times. Added to the limited space on board, especially in the more productive trawl and purse seine vessels, this may lead to practical difficulties in relation to compliance. Most of the respondents estimate that there are no realistic possibilities of utilizing the formerly discarded fish in the short term, because of the lack of adequate infrastructure on land Furthermore, the possible utilization types foreseen in the regulation will not help offset the costs of bringing former discards to land. The outcomes of this study have confirmed the implementation difficulties of the landing obligation, especially when the fishing industry cannot expect any medium to long-term benefits.

Using thirteen microsatellite loci for Mullus barbatus and Mullus surmuletus collected in the Mediterranean Sea, the biogeographic boundaries, genetic distribution among and within basins and the impact of prolonged exploitation in both species were investigated as a basis for understanding their population dynamics and for improving Mullus spp. stock management. Different level of diversity indices among these co-occurring species were obtained, with M. barbatus showing higher allele richness and higher mean observed and expected heterozygosity than M. surmuletus. Reduced contemporary effective population size (Ne) and M-ratio values found in both species likely reflects recent demographic changes, due to a combination of high fishing pressures, habitat fragmentation and naturally occurring fluctuations in population size. Different patterns of genetic connectivity among populations sampled within the Mediterranean were observed for both species. Higher genetic structure was found for M. barbatus as o

The Mediterranean Sea is characterized by large scale gradients of temperature, productivity and salinity, in addition to pronounced mesoscale differences. Such a heterogeneous system is expected to shape the population dynamics of marine species. On the other hand, prevailing environmental and climatic conditions at whole basin scale may force spatially distant populations to fluctuate in synchrony. Cephalopods are excellent case studies to test these hypotheses owing to their high sensitivity to environmental conditions. Data of two cephalopod species with contrasting life histories (benthic octopus vs nectobenthic squid), obtained from scientific surveys carried out throughout the Mediterranean during the last 20 years were analyzed. The objectives of this study and the methods used to achieve them (in parentheses) were: (i) to investigate synchronies in spatially separated populations (decorrelation analysis); (ii) detect underlying common abundance trends over distant regions (dynamic factor analysis, DFA); and (iii) analyse putative influences of key environmental drivers such as productivity and sea surface temperature on the population dynamics at regional scale (general linear models, GLM). In accordance with their contrasting spatial mobility, the distance from where synchrony could no longer be detected (decorrelation scale) was higher in squid than in octopus (349 vs 217 km); for comparison, the maximum distance between locations was 2620 km. The DFA revealed a general increasing trend in the abundance of both species in most areas, which agrees with the already reported worldwide proliferation of cephalopods. DFA results also showed that population dynamics are more similar in the eastern than in the western Mediterranean basin. According to the GLM models, cephalopod populations were negatively affected by productivity, which would be explained by an increase of competition and predation by fishes. While warmer years coincided with declining octopus numbers, areas of high sea surface temperature showed higher densities of squid. Our results are relevant for regional fisheries management and demonstrate that the regionalisation objectives envisaged under the new Common Fishery Policy may not be adequate for Mediterranean cephalopod stocks.

The illegal use of driftnets targeting large pelagic species, such as swordfish and bluefin tuna, continues to be reported in some Mediterranean countries and to cause concern due to the high risk of bycatch of protected species (chiefly marine mammals and sea turtles). In May 2014, the European Commission announced its intention to adopt a universal moratorium on driftnet fishing in EU waters. However, driftnets have been used for decades throughout the Mediterranean by countless, inshore small-scale artisanal fleets to catch small pelagic species like anchovy, sardine, and mackerel. This study was devised to collect detailed information on the technical characteristics of the small-scale driftnets used in the Mediterranean, describe the features of each net type, and identify the technical and management changes that may enable their preservation. Data analysis indicated that i) use of thin yarns and a mesh opening of less than 80 mm (or 70 mm according to a stricter approach) would allow the survival of most traditional métiers while preserving sensitive and protected species; ii) the requirement to carry on board a single gear type should be included in the regulatory framework; and iii) driftnet use within 3 miles of the coast would greatly reduce the risk of interactions with sensitive species.

The main objective of this coordinated Project has been the characterisation of the aspects related to discarding in the Italian demersal fisheries, providing qualitative and quantitative estimates of discards of species that in the near future will be subjected to landing obligation, according to the EU Reg. 1380/2013 (Art. 15) provisions. The Project investigated also socio-economic, technological and logistic aspects, related to the future management of the discards that shall be landed. The study has been carried out by four Italian Research Units (CIBM Livorno, COISPA Bari, NISEA Salerno, CNR-ISMAR Ancona) that, sharing the methodological protocols, analysed both existing and new data, collected by means of interviews and questionnaires.

The main objective of this coordinated Project has been the characterisation of the aspects related to discarding in the Italian demersal fisheries, providing qualitative and quantitative estimates of discards of species that in the near future will be subjected to landing obligation, according to the EU Reg. 1380/2013 (Art. 15) provisions. The Project investigated also socio-economic, technological and logistic aspects, related to the future management of the discards that shall be landed. The study has been carried out by four Italian Research Units (CIBM Livorno, COISPA Bari, NISEA Salerno, CNR-ISMAR Ancona) that, sharing the methodological protocols, analysed both existing and new data, collected by means of interviews and questionnaires.

The main objective of this coordinated Project has been the characterisation of the aspects related to discarding in the Italian demersal fisheries, providing qualitative and quantitative estimates of discards of species that in the near future will be subjected to landing obligation, according to the EU Reg. 1380/2013 (Art. 15) provisions. The Project investigated also socio-economic, technological and logistic aspects, related to the future management of the discards that shall be landed. The study has been carried out by four Italian Research Units (CIBM Livorno, COISPA Bari, NISEA Salerno, CNR-ISMAR Ancona) that, sharing the methodological protocols, analysed both existing and new data, collected by means of interviews and questionnaires.